I would go with the advise to do some research and not from questioning builders or vendors about their offereings and consider it "research",try to get a basic understanding of the 18th and late 17th century guns of both types from several sources, always avoid reading one book and think you "have it" with a basic backgrouns one can ask ther right questions and find many answeres in the research as well, but if questions need be asked they will be informed ones, basicaly topping off the frosting on the cake and confirming current status of many theories/opinons from many years ago, there is no shortage of incorrect info in some old text and some is still being reprinted in new editions, it is not a tough task, just takes some time and the right books and often the research can become a very interesting part of the hobby and there are many well studied folks here willing to share with those who have a sincere desire to learn, have fun and enjoy the journey.